I could make a pretty strong case for either one, really. Joe Montana was the most efficient, to be sure, accomplishing his 11 TDs and 0 INTs in about 40 fewer passes than Flacco. He also had 300 fewer yards or so, but works out to about the same yards per attempt as Flacco. His yards per completion was 12.3, and Flacco's was 15.6, so Flacco definitely relied more on making the big play, and it resulted in no shortage of spectacular highlight reel plays, while Montana had a couple of those, most of his throws were routine and efficient, not spectacular and unlikely.

What kind of road did they have to take to get to their eye-popping stat lines?

1989 49ers - 3 Games

2 games at home, 0 on the road
Defense allowed 26 points (8.7 points per game)
Defense allowed 708 yards (236 yards per game)
Defense had 12 takeaways (4 per game)
Defense allowed less than 4 yards per play
Defense held opposing QBs to: 58/119, 615 Yards, 0 TD, 9 INT = 48.7%, 5.17 Y/A, 32.7 QB Rating
Running game support: 153 yards per game, 1.25 TDs per game, over 4.2 yards per carry, 21.8 carries per TD


2012 Ravens - 4 Games

1 game at home, 2 on the road
Defense allowed 88 points (22 points per game)
Defense allowed 1713 yards (428.3 yards per game)
Defense had 10 takeaways (2.5 per game)
Defense allowed more than 5.4 yards per play
Defense held opposing QBs to: 101/179, 1146 Yards, 5 TD, 6 INT = 56.4%, 6.40 Y/A, 71.1 QB Rating
Running game support: 131 yards per game, 0.75 TDs per game, under 4.1 yards per carry, 42.7 carries per TD


Obviously the fact that Joe Flacco had to play 2 of his games on the road adds a lot more impressive flair to his résumé than Montana not having to go on the road at all. The difference in defense is also staggering. 4 takeaways per game for the 49ers in HUGE. 236 yards per game and less than 4 yards per play allowed is also a monstrous achievement for that defense. And then he also got more efficiency out of his running backs.

These factors all certainly make it easier on a quarterback. I wish I could have found drive info on the 1989 games, like starting field position for each drive, etc., but I couldn't find it. Given the takeaways and extremely stingy defense that the 49ers had in those playoffs, I'd wager that Montana was given very favorable field position throughout. Flacco was definitely not given favorable field position in his games, and he was forced to do more work, throw the ball more, and put the games in his hands. Montana just cruised along while all his supporting pieces and defense played at an equally high level to his own performance, which makes it easier on everyone when the whole team is working like a well oiled machine.

Given all that, I'd honestly have to say that in my opinion Flacco had the most impressive post-season in NFL history, but it's damn close to Montana's nearly statistically perfect 1989.